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Doolittle, Diane M.

Diane M. Doolittle

Direct Tel: +1 650-801-5007, Direct Fax: +1 650-801-5100
Silicon Valley
Tel: +1 650 801 5000 Fax: +1 650 801 5100

Diane Doolittle serves as Co-Chair of the firm's National Trial Practice Group. She litigates and tries high-stakes complex commercial, intellectual property and white collar cases.  Ms. Doolittle has tried more than 70 cases and won 92%.  She is repeatedly recognized as one of the leading trial lawyers in the United States. Law360 selected her for its inaugural award of  "Top Female Trial Attorney," one of only 15 women nationally.  In 2024, Lawdragon named her one of “500 Leading Lawyers in America.”  Each year for more than the last 10 years, she has been chosen by the San Francisco and Los Angeles Daily Journals as a "Top Women Lawyer" in California.  She has been repeatedly recognized by The Recorder as one of the "Women Leaders in Tech Law."

Ms. Doolittle has tried a wide variety of complex disputes, with tens or hundreds of millions of dollars in dispute, in state and federal courts across the country.  The cases cover subjects as diverse as misappropriation of trade secrets, trademark, antitrust, fraud, breach of contract, breach of fiduciary duty, unfair competition, extortion, and insurance coverage.  She has tried multiple employment cases involving allegations of discrimination, harassment and wrongful discharge.  Ms. Doolittle also has extensive experience trying criminal cases, from street crimes to white collar crimes.  Because of her unique trial skills, Ms. Doolittle is often engaged in the weeks or months before trial, specifically to act as trial counsel.

As a former prosecutor, Ms. Doolittle brings special expertise to, and spends a significant amount of time, defending corporations, officers and directors in parallel civil and criminal matters, including under the False Claims Act, the federal securities laws, and the FCPA.  She also litigates intellectual property disputes, including cutting-edge disputes over the intersection of intellectual property law and the Internet.

Ms. Doolittle is also a go-to lawyer for sensitive, high profile cases for companies and individuals, including those that require the development and coordination of civil, criminal, media and public relations strategies.  More recently, she has been engaged to handle sensitive #metoo cases, including by conducting internal investigations.

Ms. Doolittle lectures extensively about trial practice. Currently, she teaches trial advocacy and deposition practice at Stanford Law School.


  • Won more than $93 million in damages in a landslide win as counsel for Olaplex, a California-based start-up, against L’Oreal, the largest beauty company in the world.  Olaplex invented a patent-protected method for protecting and repairing hair during the bleaching process.  The federal jury in Delaware returned a unanimous verdict, finding that L’Oreal had willfully stolen Olaplex’s trade secrets, willfully infringed upon two Olaplex patents, and breached the parties’ NDA.  L’Oreal’s claims of patent invalidity were rejected in total, and the court doubled the non-overlapping portion of the jury’s damages award and granted attorneys’ fees and costs.  The court also granted a permanent injunction barring L’Oreal from selling the infringing products and restored Olaplex to its position as the sole provider of the revolutionary hair care product it invented.
  • Obtained dismissal of plaintiff’s claim and won a clean sweep after trial of all counterclaims on behalf of a billionaire high technology client, which included a more than $14 million judgment and permanent injunction against plaintiff for extortion, fraud, breach of fiduciary duty, invasion of privacy, and civil harassment.
  • Won a plaintiff’s judgment of more than $23 million for national medical device company after two-week trial in Northern District of California against one of its former directors for breach of fiduciary duty for usurping a corporate opportunity.
  • Successfully defended Pfizer in two lengthy trade secret trials lasting over 2 months in Santa Clara County Superior Court; defeated 152 of 159 trade secrets claims and reduced damages from an original claim of $1 billion in damages, to a jury award of just $165,000.
  • Won two separate trials in Orange County Superior Court for a billionaire technology entrepreneur accused of wrongfully terminating his estate manager in retaliation for testifying against him in grand jury proceedings, as well as denying her overtime pay. 
  • Won a defense verdict following a jury trial in Los Angeles County Superior Court on behalf of a billionaire real estate developer who was accused of fraudulently denying his children more than $150 million in child support.  Argued and successfully defended defense verdict before the California Court of Appeal.
  • Won a defense judgment in federal court in the Central District of California on behalf of The Home Depot in a case alleging misappropriation of confidential and trade secret information.
  • Won a defense verdict in a two-week antitrust trial seeking hundreds of millions in damages in the Southern District of New York on behalf of a national lawn and garden marketing company.
  • Won more than $10 million jury verdict in a two-week trial for breach of contract in the Southern District of Ohio on behalf of a national lawn and garden marketing company.
  • Won a defense award following a JAMS international arbitration on behalf of Oracle Corporation, where Oracle's former Saudi Arabian joint venture partner had sued for fraud and breach of contract under Saudi law seeking tens of millions of dollars.
  • Won a defense verdict following a six-week jury trial in San Francisco Superior Court on behalf of investment bank Jefferies & Co. in which the plaintiff, a highly compensated investment banker, alleged wrongful termination and discrimination. The verdict was nominated for "Verdict of the Month" by The National Law Journal.
  • Won a plaintiffs’ judgment on all claims after trial in Los Angeles County Superior Court on behalf of the CEO of a large, public company in a wrongful death case where the plaintiff’s daughter died of a drug overdose after defendant failed to summon medical care.
  • Won a defense award following a six-week trial in an administrative enforcement action brought by the California Department of Managed Health Care against Kaiser Foundation Health Plan.
  • Obtained a favorable settlement after six weeks of jury trial in Fresno County Superior Court on behalf of a large security company and its CEO accused of fraud, breach of partnership, and breach of contract.
  • Obtained favorable settlement after four weeks of jury trial in Sacramento Superior Court for a national insurance company, where plaintiff claimed that the insurance company failed to reimburse $135 million incurred in cleaning up a major Superfund site.
  • Boalt Hall School of Law, University of California, Berkeley
    (J.D., 1989)
  • Institut d'Etudes Politiques, Aix-en-Provence, France
    (Certificate, 1986)
  • Princeton University, Woodrow Wilson School of Public and International Affairs
    (A.B., cum laude, 1985)
  • The State Bar of California
  • The State Bar of Colorado
  • Office of the District Attorney, Santa Clara County:
    • Senior Trial Attorney, 1993-1998
  • Law Clerk to the Hon. Ronald M. Whyte:
    • United States District Court, Northern District of California, San Jose Division, 1992 
  • From 2009 to 2024, Ms. Doolittle has been selected by the San Francisco and Los Angeles Daily Journals as one of the “Top Women Lawyers” in California.
  • For 2024, Ms. Doolittle has been ranked by Lawdragon 500 Leading Litigators in America in Complex Commercial, IP, White Collar Litigation.
  • In 2022, Ms. Doolittle was ranked in Chambers USA in California for Litigation: General Commercial: The Elite.
  • In 2020 to 2023,  Lawdragon named Ms. Doolittle one of “500 Leading Lawyers in America" for Securities Litigation.
  • In 2019, Ms. Doolittle was selected for the Daily Journal’s list of “Top Trade Secrets Lawyers."
  • In 2013, 2016, 2017, and 2019, Ms. Doolittle was selected by The Recorder as one of the “Woman Leaders in Tech Law.”
  • From 2004 to 2024, she was selected each year as a Northern California “Super Lawyer” by California Lawyer Magazine.
  • In 2012, Ms. Doolittle was named one of the fifteen “Top Female Trial Lawyers in America” by Law360.
  • Association of Business Trial Lawyers (ABTL):  President 2016, Vice President 2015, Treasurer 2014, Secretary 2013, Program Chair 2009 and 2010, Board of Governors 2007 to 2016.
  • Instructor, Stanford University Law School, Trial Advocacy Program, 2000 to present.
  • Northern District of California Standing Committee on Professional Responsibility, 2010 to 2014.
  • Lawyer Representative, Ninth Circuit Judicial Conference, 2005 – 2007. 
  • Lawyer Representative, Northern District of California, 2005 – 2007.  
  • Instructor, National Institute of Trial Advocacy (NITA), 1994 – 2009.
  • Adjunct Professor, Santa Clara University School of Law, Trial Advocacy, 1996 – 1999.